pwm: Return -ENODEV if no PWM lookup match is found

When looking up a PWM using the lookup table, assume that all entries
will have been added already, so failure to find a match means that no
corresponding entry has been registered.

This fixes an issue where -EPROBE_DEFER would be returned if the PWM
lookup table is empty. After this fix, -EPROBE_DEFER is reserved for
situations where no provider has yet registered for a matching entry.

Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c
index b8f6c309c160..d24ca5f281b4 100644
--- a/drivers/pwm/core.c
+++ b/drivers/pwm/core.c
@@ -738,8 +738,10 @@ struct pwm_device *pwm_get(struct device *dev, const char *con_id)
                 }
         }
 
-        if (!chosen)
+        if (!chosen) {
+                pwm = ERR_PTR(-ENODEV);
                 goto out;
+        }
 
         chip = pwmchip_find_by_name(chosen->provider);
         if (!chip)